Swaging-stock for drills



(No Model.)

A. LAUNDRY & H. H. WARRENL SWAGING STOCK FOR DRILLS.

6. 428,498. Patented May 20, 1890.

UNITED STATES PATENT A OFFICE.

ANDREW LAUNDRY, OF CCTE ST. PAUL, QUEBEC, CANADA, ANl) HENRY.

HARRISON \VARREN, OF MASSENA, NElV YORK.

SWAGlNG-STOCK FOR DRILLS.

SPECIFICATION forming part of Letters Patent No. 428,498, dated May 20, 1890. Application filed February 24, 1890. Serial No. 341,424. (No model.)

To all whom it may concern.-

Be it known that we, ANDREW LAUNDRY, a subject of the Queen of Great Britain, residing at Cote St. Paul, in the District of Montreal and Province of Quebec, Canada, and HENRY HARRISON WARREN, a citizen of the United States, residing at Massena, in the county of St. Lawrence and State of New York, have jointly invented new and useful Improvements in Apparatus for Forming Spirals; and we do hereby declare that the following is a full, clear, and exact description of the same.

Our present invention has reference to further improvements on the invention for which Letters Patent No. 382,710 were granted to us May 15, A. D. 1888, to adapt the invention thereby patented to form twistdrills and similar spiral forms, also to form two such drills at one rolling operation with greater ease and accuracy, and also to produce as far as possible a lengthening effect upon the round bars being converted into spirals.

In the drawings hereunto annexed similar letters of reference indicate like parts.

Figure 1 is a face view of one of the swage and rolling dies a. Fig. 2 is a vertical section on line 50, Fig. 1, of a pair of swage and rolling dies at, placed in proper relative posia are the swage and rolling dies. These are constructed both alike, and are each pro vided with any desired number of ribs d, the first one of which 6 is very short, and they increase regularly in length down to the line m, where the regular increase in length of the ribs d is very considerably diminished for the purpose of causing a finer finish to the spiral grooves that are swaged by the projections (Z in the bar I); or, in other words, the projections (Z, from the first edown to the line 00', rough-out the grooves, and the remaining ribs on the other side of the line at, while they slightly increase the length of the spiral grooves, impart a finer finish, especially to the end of it. The ends of the ribs 0 are terminated in a more or less acute bevel, as shown'in Figs. 3and 4,011112LY112IV6 a rounded configuration, as shown in Fig. 5, or any other beveled configuration desired, the configuration being made to agree with What is desired to be imparted to the ends of the spiral grooves formed in the bar. Between the ribs spaces f are formed of such width and configuration as may be desired for the spiral being formed.

Although the ribs 1) are shown in Fig. 1 as being straight, they may be slightly curved, if desired, as shown by the dotted S-curved line 00.

As shown, all the ribs are of equal size in cross-section; but, if desired, the ribs 6 may be made slightly smaller than the others, or the ends of each of the swage rolling-dies may be slightly curved off, as shown by the line h in Fig. 2, which will come to the same thing, and will also assist the body or bar of 7 5 metal Z) to be entered freely between the dies at 2 in Fig. '7, 3 being taken to be the point of release, the swage and rolling-dies abeing arranged to act together, as shown in Fig. 1 of the said Patent No. 382,710, and described therein. The dies a may be either vertically or horizontally situated, as desired.

After the bar of metal has been acted upon by the dies at, it is by any ordinary means as at present in use parted at i, Fig. 6, forming 8 5 it into two twist-drills, as the surfaces 70, one on each side of the ribs form solid ends Z to the bars that are thus rolled into a spiral. \Vhat we claim is as follows: i 1. The combination of the swaging and rolling dies a, each having ribs cl, as described, metal placed between them, the Whole subof increasing length, with spaces f arranged stantially as described.

face to face and caused to reciprocate and to ANDREWV LAUNDRY. act in parallel planes upon the bar of metal HENRY HARRISON XVARREN. 5 placed between them, substantially as deitnesses to the signature of Andrew scribed. Laundry:

2. The combination of the swaging and roll- CHARLES G. (3. SIMPSON, ing dies (0, each having diagonal parallel ribs JOHN MORRISON.

'I0 or margins 70 70, one at each side of the ribs, rison Varren:

arranged face to face and caused to recipro- V. G. SNAITH, cate and act in parallel planes upon a bar of 1 V. P. DALY.

dof increasing length, spaces f, and surfaces \Vitnesses to the signature of Henry Har- 

